text: """
  Email message and email sending related helper functions.
  """
  
  
  from builtins import object
  import socket
  
  
  # Cache the hostname, but do it lazily: socket.getfqdn() can take a couple of
  # seconds, which slows down the restart of the server.
  class CachedDnsName(object):
      def __str__(self):
          return self.get_fqdn()
  
      def get_fqdn(self):
          if not hasattr(self, '_fqdn'):
              self._fqdn = socket.getfqdn()
          return self._fqdn
  
  DNS_NAME = CachedDnsName()
  